A novel broadband circularly polarization microstrip antenna based on negative refraction circuit

Based on the negative refraction circuit theory,a novel broadband Power Divider and Phase Shifter which is constructed by conventional transmission line with lumped-element series capacitors and shunt inductors is proposed in this paper.And the realization method of broadening impedance and axis ratio bandwidth is analyzed.A microstripe antenna which central frequence is 1.268GHz is designed,and the axis ratio bandwidth achieved 52.37percent.The VSWR is below 2 in the AR bandwidth.